8008243: Zero: implement fast-bytecodes [Was: Re: [RFC] Fast-bytecodes for Zero]

[Roman Kennke]

Hi David,

Am Freitag, den 15.02.2013, 17:25 +1000 schrieb David Holmes:
> There's a lot of changes to shared code here - what is the impact on 
> non-zero platforms?

The changes to shared code are in bytecodeInterpreter.cpp, which is, to
my knowledge, only used by Zero. *If* there are other interpreters that
use it (maybe in closed trees?) they would most likely just pick up and
benefit from the improvements. But of course, I cannot tell...

Regards,
Roman

> Thanks,
> David
> 
> On 15/02/2013 4:51 AM, Christian Thalinger wrote:
> > I've filed:
> >
> > 8008243: Zero: implement fast-bytecodes
> >
> > -- Chris
> >
> > On Feb 13, 2013, at 11:40 AM, Roman Kennke <rkennke at redhat.com> wrote:
> >
> >> The following change implements support for the following fast-bytecodes
> >> in the Zero interpreter:
> >>
> >> fast_agetfield
> >> fast_bgetfield
> >> fast_cgetfield
> >> fast_dgetfield
> >> fast_fgetfield
> >> fast_igetfield
> >> fast_lgetfield
> >> fast_sgetfield
> >> fast_aputfield
> >> fast_bputfield
> >> fast_cputfield
> >> fast_dputfield
> >> fast_fputfield
> >> fast_iputfield
> >> fast_lputfield
> >> fast_sputfield
> >> fast_aload_0
> >> fast_iaccess_0
> >> fast_aaccess_0
> >> fast_faccess_0
> >> fast_iload
> >> fast_iload2
> >> fast_icaload
> >> fast_invokevfinal
> >>
> >> All together this leads to a speedup of the interpreter of about 25%.
> >>
> >> Some notes:
> >> - I extracted the JVMTI related blocks into a macro to avoid repetition.
> >> - The field get/put opcodes are only rewritten for non-volatile
> >> non-static field access, this makes the fast one really fast (no
> >> additional branches needed), and static/volatile field accesses seem
> >> rare enough anyway.
> >>
> >> http://cr.openjdk.java.net/~rkennke/zero-fast-opcodes/webrev.00/
> >>
> >>
> >> Opinions? Can this be included in hotspot? And Can I have a bug-ID?
> >>
> >> Best regards,
> >> Roman
> >>
> >>
> >